Television Infrared Observation Satellite

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TIROS 6 satellite
First TV image of Earth from space

TIROS, or Television Infrared Observation Satellite, is a series of early weather satellites launched by the United States, beginning with TIROS-1 in 1960. TIROS was the first satellite that was capable of remote sensing of the Earth, enabling scientists to view the Earth from a new perspective: space.[1] The program, promoted by Harry Wexler, proved the usefulness of satellite weather observation, at a time when military reconnaissance satellites were secretly in development or use. TIROS demonstrated at that time that "the key to genius is often simplicity".[2]

The 270 lb (122 Kg) satellite was launched into a nearly circular low earth orbit by a Thor Able rocket. Drum-shaped with a 42 inch (1.1 m) diameter, and height of 19 inches (48 cm), the TIROS satellite carried two six-inch (15 cm) long television cameras. One of the cameras had a wide-angle lens with an f /1.6 aperture that could view an 800 mile wide area of the earth. The other camera had a telephoto lens with an f /1.8 aperture and 10 to 12 power magnification[citation needed] compared to the wide angle camera.

The satellite itself was stabilized in its orbit by spinning like a gyroscope. When it first separated from the rocket's third stage, it was spinning at about 136 revolutions per minute (rpm). To take unblurred photographs, a de-spin mechanism slowed the satellite down to 12 rpm after the orbit was accomplished.

The camera shutters made possible the series of still pictures which were stored and transmitted back to earth via 2-watt FM transmitters as the satellite approached one of its ground command points. After transmission, the tape was erased or cleaned and readied for more recording.


TIROS continued as the ESSA TIROS Operational System, and was eventually succeeded by the NOAA ITOS (Improved TIROS Operational System), or TIROS-M, and then by the TIROS-N and Advanced TIROS-N series of satellites. The naming of the satellite can become confusing because the satellites share the same name as the over-seeing organization, such as ESSA & ESSA 1 and NOAA & NOAA M. NOAA-N Prime is the last in the TIROS series of NOAA satellites that observe Earth’s weather and the environment.[3]

Participants in this satellite project included the US National Aeronautics and Space Administration, United States Army Signal Research and Development Lab, Radio Corporation of America, the United States Weather Bureau, and the United States Naval Photographic Interpretation Center.[4]

  • TIROS-1 (A): launched April 1, 1960, suffered electrical system failure on June 15, 1960
  • TIROS-2 (B): launched November 23, 1960, failed January 22, 1961
  • TIROS-3 (C): launched July 12, 1961, deactivated February 28, 1962
  • TIROS-4 (D): launched February 8, 1962, failed on June 30, 1962 (both cameras failed earlier)
  • TIROS-5 (E): launched June 19, 1962, failed on May 13, 1963
  • TIROS-6 (F): launched September 18, 1962, failed October 21, 1963
  • TIROS-7 (G): launched June 19, 1963, deactivated June 3, 1968
  • TIROS-8 (H): launched December 21, 1963, deactivated July 1, 1967
  • TIROS-9 (I): launched January 22, 1965, failed February 15, 1967. First Tiros satellite in near-polar orbit
  • TIROS-10 (OT-1): launched July 2, 1965, deactivated July 31, 1966

As of June 2009, all TIROS satellites launched between 1960 and 1965 (with the exception of TIROS-7) were still in orbit.[5]

TIROS Operational System


  • TIROS-M (ITOS-1): January 23, 1970 launch
  • NOAA-1 (ITOS-A): December 11, 1970 launch
  • ITOS-B October 21, 1971 launch; unusable orbit
  • ITOS-C
  • NOAA-2 (ITOS-D): October 15, 1972 launch
  • ITOS-E July 16, 1973 launch, failed to orbit
  • NOAA-3 (ITOS-F): November 6, 1973 launch
  • NOAA-4 (ITOS-G): November 15, 1974 launch
  • NOAA-5 (ITOS-H): July 29, 1976 launch


  • TIROS-N: Launched October 13, 1978
  • NOAA-6 (A): Launched June 27, 1979
  • NOAA-B: Launched May 29, 1980. It failed to achieve a usable orbit because of a booster engine anomaly.[3]
  • NOAA-7 (C): Launched June 23, 1981

Advanced TIROS-N

  • NOAA-8 (E): NOAA-E was launched March 28, 1983 out of sequence (before NOAA-D) to get the first US search and rescue satellite operational.[3]
  • NOAA-9 (F): Launched December 12, 1984
  • NOAA-10 (G): Launched September 17, 1986
  • NOAA-11 (H): Launched September 24, 1988
  • NOAA-12 (D): NOAA-D was launched May 14, 1991 and deactivated on August 10, 2007 setting an extended lifetime record of over 16 years.[3]
  • NOAA-13 (I): Launched August 9, 1993; two weeks after launch the spacecraft suffered a catastrophic power system anomaly.[3]
  • NOAA-14 (J): Launched December 30, 1994
  • NOAA-15 (K): Launched May 13, 1998
  • NOAA-16 (L): Launched September 21, 2000
  • NOAA-17 (M): Launched June 24, 2002
  • NOAA-18 (N): Launched May 20, 2005
  • NOAA-19 (N Prime): Launched February 6, 2009[6]


  1. ^ "Space-Based Remote Sensing of the Earth: A Report to the Congress". NASA. NASA Technical Reports Server. Retrieved 4 October 2011. 
  2. ^ Modern Mechanix: How Tiros Photographs the World
  3. ^ a b c d e "NOAA-N Prime". NP-2008-10-056-GSFC. NASA Goddard Space Flight Center. 16 December 2008. Retrieved 8 October 2010. 
  4. ^ EXPLORES! (EXPloring and Learning the Operations and Resources of Environmental Satellites!)
  5. ^ "U.S. Space Objects Registry". Bureau of Oceans and International Environmental and Scientific Affairs. Retrieved 2009-06-25. 
  6. ^ Justin Ray (February 6, 2009). "History Abounds in Launch of Crucial Weather Satellite". Spaceflight Now. Retrieved 25 October 2010. A last-of-its-kind weather observatory... 

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